Japanese Patent Application Laid-Open No. 6-112386 describes a technique related to diode parts having the following structure. That is, two slug leads each of which is obtained by junction of a CP line used as an external lead to a Dumet wire used as an internal lead are prepared, and the Dumet wires of the two slug leads are inserted into the cylinders of cylindrical sealing members (glass sleeves) consisting of a glass material from both the ends of the cylinder, and a single diode is sealed in a cavity formed by the Dumet wires and the sealing material.